Flowable compositions such as molding compounds and solder paste are commonly used in the semiconductor industry for a variety of applications, e.g., formation of packages and electrical connections. As microelectronic devices and packaging have become increasingly miniaturized, there is a growing need to control placement of such flowable compositions with greater precision. Accordingly, the tools associated with the application of flowable compositions are evolving to meet these challenges.
Stencils, for example, represent a class of tools known for their use in applying flowable compositions such as inks and pastes on surfaces of substrates. In particular, stencils may be used to form flip-chip packages which require protrusions such as metal bumps or balls to be placed or fabricated on each bonding pad of a substrate, e.g., a semiconductor die. Such protrusions can be solder or another metal. “Bumping” may be performed when the semiconductor dies are still connected to one another in wafer form. Typically, solder features are deposited via stencil printing, and the deposited features are reflowed to form spherical balls, or bumps. Similarly, flowable compositions such as molding compounds also require tools such as molds, injectors, and the like to control their placement.
As features associated with stencils, molds, and other tools for controlling the placement of flowable compositions become smaller, surface forces become increasingly dominant over bulk fluid effects. Accordingly, at or below certain feature sizes, flowable compositions undesirably and/or uncontrollably adhere to the surfaces of the tools. In turn, rework or more costly alternatives may be required to achieve the required precision for the placement of the flowable compositions.
Polyceramics are a class of materials containing both polymeric and ceramic components. For example, polyacrylic acid may be reacted with silicate glass to form a polyceramic material. In some cases, a polyceramic may be formed through in situ polymerization. In dental applications, for example, a precursor polyceramic composition may undergo radiation initiated polymerization where it is applied to form polyceramic materials in situ. See, e.g., U.S. Pat. No. 6,652,281 to Eckhardt et al. Alternatively, polyceramic coatings may be formed by spraying, brushing, wiping, or otherwise applying a layer of precursor liquid containing a solvent, and subjecting the liquid to conditions effective to form the coating. For example, precursor fluids containing chlorobenzotrifluoride as a solvent from NIC Industries Inc. (White City, Oreg.) may be applied to a surface of an item. Once the solvent is evaporated, the remaining components of the precursor liquid, under appropriate curing conditions, form a polyceramic coating on the surface.
Previously, polyceramic coatings have been applied to various items such as automotive parts and firearms. In addition, polyceramic coatings have been used as a graffiti-repelling paint. More recently, as described in U.S. patent application Ser. No. 11/025,439, entitled “Semiconductor Members Having A Halogenated Polymeric Coating And Methods For Their Formation,” filed on Dec. 29, 2004, inventor Jesse Thompson, polyceramics coatings have found new applicability in the semiconductor microelectronic device industry. In particular, the described polyceramic coatings have been found to increase the strength of semiconductor members such as those used to form microelectronic chips and dies.
Nevertheless, there exist additional opportunities in the art to exploit the physical, mechanical, and chemical properties of polyceramic coating for apparatuses and tools associated with the semiconductor industry. In particular, a new use has been discovered for polyceramic coatings in the context of tooling for manipulating flowable compositions commonly used in microelectronic packaging to effect greater control over feature dimensions.